Background
Windy City Innovations, LLC sued Facebook, Inc. for patent infringement in the Northern District of California, asserting patents covering social networking features. Facebook responded by filing multiple inter partes review (IPR) petitions at the Patent Trial and Appeal Board (PTAB) challenging the asserted patents’ validity. When Facebook’s first IPR petitions were instituted, it filed additional petitions and moved to join itself to its own already-instituted proceedings—a maneuver sometimes called “self-joinder.” Facebook used this joinder mechanism to add new invalidity grounds that would otherwise have been time-barred under the AIA’s one-year deadline for filing IPR petitions, 35 U.S.C. § 315(b).
The PTAB granted Facebook’s joinder motions and allowed the new issues into the proceedings. Windy City appealed, arguing that the statute only permits a third party to join an IPR, not a petitioner joining its own proceeding, and that expanding the issues through joinder violated the statutory time bar Congress imposed to limit serial validity challenges.
The Court’s Holding
The Federal Circuit held that the IPR joinder statute, 35 U.S.C. § 315(c), does not authorize same-party joinder and does not permit joinder of new issues—including issues that would otherwise be time-barred. Writing for the court, Judge Dyk grounded the analysis in the statutory text: the provision allows “any person” who is not already a party to join an instituted IPR. A petitioner that is already a party to the proceeding is not a “person who is not already a party,” and therefore cannot invoke the joinder mechanism to expand its own pending proceeding.
The court also rejected the PTAB’s practice of permitting joinder that allowed a petitioner to add new invalidity grounds not raised in the original instituted petition. Such “issue joinder” effectively circumvented the one-year time bar Congress enacted to prevent serial, harassing challenges to issued patents. Permitting it would undermine a key structural protection of the AIA regime.
The Federal Circuit modified and reissued its opinion on September 4, 2020, following Facebook’s petition for panel rehearing and rehearing en banc. The modified opinion preserved the core holdings while remanding to the PTAB on certain subsidiary questions about the late-filed petitions.
Key Takeaways
- A petitioner cannot join itself to its own pending IPR to import new invalidity issues into the proceeding — “self-joinder” is not permitted under 35 U.S.C. § 315(c).
- IPR joinder cannot be used to add new issues or grounds that would otherwise be barred by the AIA’s one-year filing deadline; this closes a significant workaround that some petitioners had exploited.
- The decision reduces PTAB flexibility in multi-petition IPR strategies, requiring petitioners to include all desired grounds in their original, timely filed petitions.
- Patent owners gain stronger protection against serial IPR attacks because petitioners can no longer use joinder to continually inject new invalidity theories after the one-year window closes.
Why It Matters
For years, large technology companies facing patent infringement suits had used the self-joinder maneuver to mount expanded IPR challenges even after the statutory one-year window expired. Facebook v. Windy City shut down that practice, restoring a measure of repose that Congress intended when it imposed the one-year deadline. The decision forces petitioners to make their full invalidity case in the initial filing — a discipline that levels the playing field for patent owners and reduces the risk that well-resourced defendants can use procedural maneuvering to delay and expand IPR challenges indefinitely.
For patent owners, this ruling strengthens the value of surviving an initial IPR without a fully developed petitioner strategy, since adding new attacks through joinder after the deadline is no longer available. For patent challengers, it means that initial IPR strategy must be comprehensive—incomplete early petitions cannot be supplemented later through the joinder mechanism.